RT-ZD002 / RT-ZD003
25 MHz Active Differential Probes
RT-ZD002 (1337.9700.02)
RT-ZD003 (1337.9800.02)
These probes are in compliance with IEC-61010-031 CAT III, Pollution Degree 2
1. Safety Terms and Symbols
Terms appear in this manual:
WARNING. Warning statements identify conditions or practice that
could result in injury or loss of life.
CAUTION. Caution statements identify conditions or practice that
could result in damage to this product or other property.
Safety Symbols
Connect to safety earth ground using the wire recommended in
the user’s manual.
High voltage danger
The symbol on an instrument indicates that the user should refer
to the operating instructions located in the manual.
2. General Safety Summary
Review the following safety precautions to avoid injury and prevent damage to this probe
or any products connected to it.
Observe Maximum Working Voltage
To avoid any injury, do not use the probe under the condition that the voltage between
both input leads and earth is above 1000 Vrms CAT III. This voltage rating applies to
both probes and both settings 1/10 & 1/100 (RT-ZD002) and 1/20 & 1/200 (RT-ZD003).
Must be Grounded
This probe is grounded with the shell of BNC connector and an auxiliary grounding
terminal, through the grounding conductor of the power cord of the measurement
instrument. Before making connections to the input leads of this probe, ensure that the
output BNC connector is attached to the BNC connector of the measurement instrument
and the measurement instrument is properly grounded.
Do Not Operate Without Covers
To avoid electric shock or fire hazard, do not operate this probe with covers removed.
Do Not Operate in Wet/Damp Conditions
To avoid electric shock, do not operate this probe in wet or damp conditions.
Do Not Operate in Explosive Atmosphere
To avoid injury or fire hazard, do not operate this probe in an explosive atmosphere.
Avoid Exposed Circuit
To avoid injury, remove jewelry such as rings, watches, and other metallic objects. Do not
touch exposed connections and components when power is present.
Use Proper Power Source
To ensure the function of the probe, use four AA cells or the supplied USB power cord.
Do not operate this probe from a power source that applies more than the voltage
Do Not Operated With Suspected Failures
If you suspect there is damage to this probe, have it inspected by qualified service
3. Description
By enabling conventional oscilloscopes to display and measure in-circuit waveforms that
are referenced to high common mode voltages, the differential probe extends the
measurement capability of oscilloscopes in electronic power converters, inverters, motor
speed controls, switch mode power supplies, and many applications.
4. Installation
a. Simply plug-in the BNC output connector to the vertical input of a general purposed
oscilloscope or other measurement instrument. The measurement instrument must be
ground referenced.
b. Connect an appropriate power source to the probe or enter the batteries, then turn it on.
c. Select the proper attenuation ratio. When measuring signals below 70 V or 140 V, switch
the attenuation ratio to 1/10 (RT-ZD002) or 1/20 (RT-ZD003) in order to get higher resolution
and less noise. Otherwise, set the attenuation ratio to 1/100 (RT-ZD002) or 1/200
(RT-ZD003) when measuring signals up to 700 V or 1400 V.
WARNING. To protect against electric shock, use only the
accessories supplied with this probe.
d. Using the appropriate probe accessories, connect the inputs to the circuit under test.
CAUTION. This probe is built to carry out differential measurements
between two points on the circuit under test.
This probe is not meant for electrically insulating the
circuit under test and the measuring instrument.
5. Appearance
The differential probe looks as follows.
a. Output cable
The BNC output connector and an auxiliary grounding
terminal are connected to the oscilloscope.
b. Input leads
The input leads of the differential probe connect to
appropriate accessories with 4 mm sockets.
The accessories are connected safely to test points in the
c. Connection accessories
circuit under test.
6. Available Power Sources
• 4 x AA batteries
• USB Power Cord, for oscilloscopes which offer USB connector.
The supplied voltage must be less than 12 V and greater than 4.5 V, otherwise the
probe could be damaged or can’t be operated properly.
Polarity is “+” inside and “–” outside. For wrong polarity a built-in circuit protects the
probe, no danger or damage will occur.
When the voltage of the cells become too low, the power indicator on the front panel will
7. Accessories supplied
• Grabber red and black
• Alligator clip red and black
• USB power cord
• Trimming tool
• Instruction manual
• Certificate of calibration
8. Specifications
DC to 25 MHz (-3 dB)
DC to 25 MHz (-3 dB)
Attenuation Ratio
1:10 / 1:100
1:20 / 1:200
±2 % (meas.)
±2 % (meas.)
Rise Time
14 ns (calculated from bandwidth)
14 ns (calculated from bandwidth)
Input Impedance
8 MΩ // 2.75 pF differential
4 MΩ // 5.5 pF each side to ground
8 MΩ // 2.75 pF differential
4 MΩ // 5.5 pF each side to ground
Input Voltage
- Differential Range
1:10 ±70 V (DC+peak AC)
1:100 ±700 V (DC+peak AC)
1:20 ±140 V (DC+peak AC)
1:200 ±1400 V (DC+peak AC)
or 1000 Vrms
Input Voltage
- Common Mode Range
1:10 and 1:100
±700 V (DC+peak AC)
1:20 and 1:200
±1400 V (DC+peak AC)
or 1000 Vrms
Maximum Input Voltage
(each side to ground)
1000 V CAT III
1000 V CAT III
Output Voltage Swing
±7 V (into 50 kΩ load)
±7 V (into 50 kΩ load)
Output Voltage Offset
±5 mV (meas.)
±5 mV (meas.)
Output Voltage Noise
0.7 mVrms (meas.)
0.7 mVrms (meas.)
Oscilloscope Input
1 MΩ
1 MΩ
CMRR (meas.)
-86 dB @ 50 Hz, -66 dB @ 20 kHz
-80 dB @ 50 Hz, -60 dB @ 20 kHz
Operating Temperature
-10 °C to 40 °C
-10 °C to 40 °C
Storage Temperature
-30 °C to 70 °C
-30 °C to 70 °C
25 % to 85 % RH
25 % to 85 % RH
Power Requirements
- Standard
4 x AA Cells
4 x AA Cells
Power Requirements
- Optional
4.5 V to 12 V, 360 mW
4.5 V to 12 V, 360 mW
Length of BNC Cable
95 cm
95 cm
Length of Input Leads
45 cm
45 cm
400 g (probe and PVC jacket)
400 g (probe and PVC jacket)
Dimensions (LxWxH)
170 mm x 63 mm x 21 mm
170 mm x 63 mm x 21 mm
Derating Curve
The derating curve of the absolute maximum input voltage in common mode is shown as
follows and valid for both models RT-ZD002 and RT-ZD003.
Voltage (V rms)
Frequency (Hz)
10. Inspection Procedure
a. Connect the BNC output connector to the vertical input of a general purpose
b. Install four AA cells or connect an appropriate power lead.
c. Set the oscilloscope input coupling to 1 MΩ, DC and to 1V/div. Center the trace on the
d. Connect the inputs of the probe to power lines, using an appropriate power socket to
4 mm adapter.
e. Set the range of the probe to 1/100 (RT-ZD002) or 1/200 (RT-ZD003).
f. Then, a 50 Hz/ 60 Hz sine-wave of proper amplitude will be displayed on the screen of
the oscilloscope and this means the probe is working properly.
11. Cleaning
Use a soft cloth to clean the dirt. Prevent damage to probe.
a. Avoid immersing the probe.
b. Avoid using abrasive cleaners.
c. Avoid using chemicals contains benzene or similar solvents.
12. WEEE / RoHS Directives
This electronic product is subject to disposal and recycling regulations that vary by
country and region. Many countries prohibit the disposal of waste electronics
equipment in standard waste receptacles.
13. Manufacturer
For comprehensive information about Rohde and Schwarz, please visit our homepage on
the R&S Internet (
For queries regarding technical aspects of our products, please contact our customer
support at
For international services, please contact our service partners at
For additional questions, please contact our headquarters in Munich.
Mühldorfstraße 15
D-81671 München
Phone: +49 (89) 41 29 - 0
Fax: +49 (89) 41 29 - 12 164